package com.example.web;

import com.example.pojo.Book;
import com.example.pojo.Cart;
import com.example.pojo.CartItem;
import com.example.service.BookService;
import com.example.service.impl.BookServiceImpl;
import com.example.utils.WebUtils;
import com.google.gson.Gson;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

public class CartServlet extends BaseServlet {
    private BookService bookService = new BookServiceImpl();

    /**
     * 修改商品数量
     *
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */
    protected void updateCount(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 获取请求的参数 商品编号 、商品数量
        int id = WebUtils.parseInt(req.getParameter("id"), 0);
        int count = WebUtils.parseInt(req.getParameter("count"), 1);
        // 获取Cart购物车对象
        Cart cart = (Cart) req.getSession().getAttribute("cart");
        System.out.println(id + "--------" + count);
        if (cart != null) {
            // 修改商品数量
            cart.updateCount(id, count);
            // 重定向回原来购物车展示页面
            resp.sendRedirect(req.getHeader("Referer"));
        }
    }

    /**
     * 清空购物车
     *
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */
    protected void clear(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        Cart cart = (Cart) req.getSession().getAttribute("cart");
        if (cart != null) {
            cart.clear();
            resp.sendRedirect(req.getHeader("Referer"));
        }
    }

    /**
     * 删除商品项
     *
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */
    protected void deleteItem(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        int id = WebUtils.parseInt(req.getParameter("id"), 0);
        Cart cart = (Cart) req.getSession().getAttribute("cart");
        if (cart != null) {
            cart.deleteItem(id);
            resp.sendRedirect(req.getHeader("Referer"));
        }
    }

    /**
     * 加入购物车
     *
     * @param req
     * @param resp
     * @throws ServletException
     * @throws IOException
     */
    protected void addItem(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //获取商品编号
        int id = WebUtils.parseInt(req.getParameter("id"), 0);
        //获取图书信息
        Book book = bookService.queryBookById(id);
        //将图书信息转化为CartItem商品项
        CartItem cartItem = new CartItem(book.getId(), book.getName(), 1, book.getPrice(), book.getPrice());
        //添加商品项
        Cart cart = (Cart) req.getSession().getAttribute("cart");
        if (cart == null) {
            cart = new Cart();
            req.getSession().setAttribute("cart", cart);
        }

        cart.addItem(cartItem);
//        System.out.println(cart);
        //最后一个加入购物车的
        req.getSession().setAttribute("lastName", cartItem.getName());

        //重定向回所在页面
        resp.sendRedirect(req.getHeader("Referer"));

//        System.out.println("请求头的referer的值："+req.getHeader("Referer"));

    }

    protected void ajaxaddItem(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //获取商品编号
        int id = WebUtils.parseInt(req.getParameter("id"), 0);
        //获取图书信息
        Book book = bookService.queryBookById(id);
        //将图书信息转化为CartItem商品项
        CartItem cartItem = new CartItem(book.getId(), book.getName(), 1, book.getPrice(), book.getPrice());
        //添加商品项
        Cart cart = (Cart) req.getSession().getAttribute("cart");
        if (cart == null) {
            cart = new Cart();
            req.getSession().setAttribute("cart", cart);
        }

        cart.addItem(cartItem);
//        System.out.println(cart);
        //最后一个加入购物车的
        req.getSession().setAttribute("lastName", cartItem.getName());
        Map<String, Object> resultMap = new HashMap<String, Object>();
        resultMap.put("totalCount",cart.getTotalCount());
        resultMap.put("lastName",cartItem.getName());
        Gson gson=new Gson();
        String resultMapJsonString=gson.toJson(resultMap);
        resp.getWriter().write(resultMapJsonString);

    }
}
